What is the ERTR?

This is the "Environmentally Responsive Test Room" or as we call it the "ERTR".

The Test Room was built to demonstrate that a “smart” Sunroom can heat and cool itself and keep a comfortable interior temperature all night and all day.

The ERTR heats and cools itself by responding to the bright day sunlight & cold night air temperatures of the high altitude, dry, desert climate of New Mexico and similar parts of the American Southwest as well.

The ERTR is a highly insulated room that uses a “smart” computer control system that senses inside & outside temperatures as well as electro-mechanically operating

1. a south facing window

2. with an insulating curtain

3. and an over-head sunshade

These smart devices are used to accumulate and store heat and cold in a Thermal Mass so that the room interior stays comfortable even when the outside temperatures are not.

All of these “smart” sensors and electro-mechanical devices are controlled by a Raspberry Pi computer running the open-source home automation software Home Assistant.

The Home Assistant “front-end” automations communicate using Wi-Fi to control the multiple electro-mechanical “back-end” ERTR MCU Nodes. These “back-end” ERTR MCU Nodes are custom (but open source) electronic printed circuit board assemblies with an embedded ESP8266 node-mcu that that is programmed and controlled using the ESP-Home add-on of Home Assistant.

By using a battery charged by solar photovoltaic collectors to power the motors and all of the electronics including the local Wi-Fi network, the ERTR sunroom can run stand-alone, off-grid and without the World Wide Web, so it is an ideal way to build a Remote Cabin or as a “Green” Room Addition to a home.

We invite you to subscribe to the ERTR Chronicles and join our community of developers, owners and hobbyists who have embraced Environmentally Responsive Climate Control and share information to expand and improve this technology.